validateConfigMapOverrides skips required checks for default minVersionForCollab

[anthony-murphy]

Describe the bug

validateConfigMapOverrides() returns immediately when minVersionForCollab === defaultMinVersionForCollab. Consequently, it never consults ConfigValidationMap for any runtime option when the default is used—even when an enabled option requires a version newer than the current default.

This encourages feature-specific workarounds outside the validation map. A workaround that checks equality with defaultMinVersionForCollab is also incorrect over time: the default can advance, and such code would continue rejecting a feature after the default semantically satisfies its required version.

This was encountered while reviewing PR #27880, where inlineDetachedBlobsAsSummaryBlobs: true requires 2.115.0.

To Reproduce

Steps to reproduce the behavior:

1. Add a ConfigValidationMap entry mapping an enabled option to a version newer than defaultMinVersionForCollab.
2. Call validateConfigMapOverrides(defaultMinVersionForCollab, { option: true }, validationMap).
3. Observe that validation returns without checking the entry.

Expected behavior

The shared validation mechanism should support map-driven semantic validation against the actual default version while preserving intentional backward-compatible exceptions for existing options. Feature implementations should not need bespoke default-version checks or duplicate their required version outside the validation map.

Logs

N/A